/**
 * Copyright 2011 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.solarchallenge.server.persistence;

import javax.jdo.JDOHelper;
import javax.jdo.PersistenceManager;
import javax.jdo.PersistenceManagerFactory;

/**
 * Singleton wrapper over JDO PersistenceManagerFactory.
 * PMF should be initialized only once, and then it should be used at all
 * other places.
 *
 * @author Arjun Satyapal
 */
public class PMF {
  private static final PersistenceManagerFactory instance = JDOHelper
    .getPersistenceManagerFactory("transactions-optional");

  private PMF() {
  }

  public static PersistenceManager getPersistenceManager() {
    return instance.getPersistenceManager();
  }
}
